R: MJ coelurosaurians

["Jonathan R. Wagner" <znc14@TTACS.TTU.EDU>]

Alessandro Marisa wrote:
>From what I known about Gasosaurus there isn't a basal Coelurosauria, but is
>a basal AveTheropoda, 
        Alessandro,
        Actually, the way these taxa are defined, a "basal avetheropod"
*must* be a member of the Carnosauria or the Coelurosauria. These are
defined as:

        Avetheropoda == "The most recent common ancestor of _Allosaurus_ and
modern birds and all of its descendants"
        Coelurosauria == " Modern birds and all taxa shareing a more recent
common ancestor with modern birds than with _Allosaurus_"
        Carnosauria == " _Allosaurus_ and all taxa shareing a more recent
common ancestor with _Allosaurus_ than with modern birds"

        So, if a taxon is a member of Avetheropoda, i.e. a descentant of the
most recent common ancestor of _Allosaurus_ and modern birds, it is (almost
certainly) either more closely related to modern birds or to _Allosaurus_,
and therefore is either a "basal" carnosaur or a "basal" coelurosaur.

        Hope this helps,
        :)
        Wagner
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     Jonathan R. Wagner, Dept. of Geosciences, TTU, Lubbock, TX 79409-1053
 "Only those whose life is short can truly believe that love is forever"-Lorien